Pump.



W. A. DREWETT. PUMP.

. APPLICATION FILED JULY 18. 1911. 1 ,035, l '70. Patented Aug. 13,1912.

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PUMP.

AlfPLIoATIoN FILED JULYl. 1911.

W. A. DREWBTT.

PUMP.

APPLICATION FILED JULY 1a, 1911.

Patented Aug-13,1912.

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PUMP.

APPLICATION FILED JULY 1e, 1911.

Patented Aug. 13, 1912.

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UNITED STATES PATENT OFFICE.

WILLIAM A. DREWETT, OF NEW YORK, N. Y., ASSIGNOGR. OF ONE-HALF T0 M. T. DAVIDSON COMPANY, OF BROOKLYN, NEW YORK, A CORPORATION OF NEW YORK.

PUMP.

Specification of Letters Patent.

Patented Aug. 13, 1912.

Application filed July 18, 1911. Serial No. 639,175.

To all whom it may concern:

Be it known that LWILLIAM A. Dnnwn'rr, a citizen of the United States, and resident of the borough of Brooklyn, in the city and State of New York, have invented a new and useful Improvement in Pumps,of which the following is a specification.

My invention relates to -pumps and more particularly to intercoacting or twin pumps for maintaining a vacuum in the condenser into which an engine exhausts.

It has been found necessary in certain types of engine, for example the turbine engine, to maintain a more perfect vacuum than has hitherto been considered satisfactory, and my present invent-ion is directed to means for eiciently accomplishing this result.

A practical embodiment of my invention is represented in the accompanying drawings, in which- Figure 1 is a view of the intercoacting pumps in front elevation, partly in sect-ion, Fig. 2 is a view in side elevation, Fig. 3 is a vertical central section through the so-called dry vacuum pump, Fig. 4 is a horizontal seetlon the plane of the line A-A- of Fig. 1, Fig. 5 is a horizontal section in the plane ot' the line B-B of Fig. 1, Fig. 6 is a horizontal section in the plane of the line 0*() of Fig. 3, and Fig. 7 is a diagrammatical View showing the connections of the pumps with the engine condenser, the latter being shown in section.

The cylinder of the dry vacuum pump is denoted by l and the cylinder of the wet vacuum pump by 2. These cylinders are conveniently placed side b side, and their pistons denoted by 3 an 4, respectively, have their rods 5 and 6 connected by a walking beam 7 driven by steamcylinders 8 and 9. rllhe pistons 3 and 4 move simultaneously in opposite directions and each is provided with a gang ot' valves opening upward as is common.

The dry pump cylinder 1 is superposed on an air and vapor inlet chamber 10 and its interior is separated from the said chamber by a stationary valve plate 11 providedy with a gang ot' valves 12 opening upward.

An outletchamber 13, at the top oi the cylinder 1, is separated from the interior ot' the chamber by a stationary valve plate 14 provided with a gang of valves 'l5 opening upward. The cylinder 1 is water jacketed as is also the chamber 10, the latter being further provided with 'a wall having heat radiating ribs 1G formed thereon, the object being to provide for cooling the chamber 1() to a very low degree by circulating a cold medium about the chamber, either cold fresh or salt water or even the brine or cooling mixture from an ice plant.

rl`he cylinder 2 is provided at its top with a discharge chamber 17, separated from the interior of the cylinder by a stationary valve plate 18 provided with a gang of upwardly opening valves 19. The said cylinder 2 is super-posed on a water inlet chamber 20, separated from the interior of the cylinder by a stationary valve plate 21 provided with a gang of upwardly opening valves The outlet or compression chamber 13 at the top of the d1-y7 pump cylinder l communicates with the interior of the cylinder 2 through a conduit 23.

The air and vapor inlet chamber 10 communicates with the air and gaseous vapor within the condenser 24, see Fig. 7), through a pipe 25, terminating within the condenser at a point above the bottom of the condenser, as shown.

The water inlet chamber 20 communicates with the interior oi the condenser 24 through a pipe 26 terminating at the bottom of the condenser.

The discharge chamber 17 above the cylinder 2 con'imunicates, through an outlet 27, with the hot well, not shown.

In operation: During the downward stroke of the piston 4 and simultaneous upward stroke of the piston 3, the air and gas cous vapor, freed from moisture as far as feasible and cooled, is lifted by the piston 3 and discharged into the cylinder 2 through thc conduit 23, the pressure tending to hold the valves 15 down being materially relieved by the downward movement of the piston 4. During the downward movement of the piston 3 and upward movement oit' the piston 4, a new charge of air and gaseous vapor passes through the valves in the piston 3 and the charge oi water, air and gaseous vapor in the cylinder 2 is discharged into the chamber 17 and thence into the hot well, not shown, to be returned to the boiler in any well known or approved manner.

By discharging the dry vacuum cylinder into the wet vacuum cylinder, back pressure on the valves at the top of the cylinder 2 is very materially reduced increasing the eliiciency of the dry vacuum pump and by cooling and condensingas far as may be Athe combined atmosphere and gaseous vapor as it enters the dry vacuum pump from the condenser, the efficiency of this pump is still further increased, so that the desired increase in the degree of vacuum in the condenser is readily obtained and maintained.

The dry vacuum pump Will, from time to time, pumpthe Water of condensation from the chamber 10, as it accumulates therein. n

l. The combination with a condenser, 'of inter-coacting pumps, the deliveryA side of one pump connecting through check valves With the delivery side of another pump, a

cooling chamber in communication With the air and gaseous vapor portion of the condenser and with one of the pumps and means for placing another pump in communication With the Water portion of the condenser.

2. The combination with a coiidenser, of inter-coacting pumps in which the pistons simultaneously reciprocate in opposite directions, a cooling chamber Icommunicating through .check valves vvith one of the pumps and through a pipe with the air and gaseous vapor portion of the condenser, a pipe leading from the Water port-ion of the condenser to the other ump and a Valved conduit leading from t e delivery side of the pump with which the cooling chamber connects to the delivery side of the other pump.

3. ln combination, a condenser, a pair of inter-coacting pumps, the pistons of which move simultaneously in opposite directions, one of the pumps being connected to receive its supply from the air and gaseous vapor portion of the condenser and the other to receive its supply from the Water portion' of the condenser, a conduit leading from the delivery side of one pump to the delivery side of the other pump, a cooling chamber at the base of one of the pumps through which the air and gaseous vapor is required to pass and a water chamber at the base of the other pump.

4C. In combination, a condenser, "a pair of inter-coacting pumps, onel in communication With the air 'and gaseous vapor portion of the condenser and thev other in communication with the Water portion of the condenser, each pump being provided With a stationary valve plate at its head and foot, valves seated in the said plates, a conduit connecting the ldelivery sides of the two pumps and a cooling chamber interposed between the' condenser and the pump in communication with the air and gaseous vapor portion .thereof through Which the air and gaseous Vapor is required to pass.

In' testimony, that I claim the foregoing as my invention, I have signed my name in presence of two Witnesses, this twenty-ninth day of June 19111 WM. A. DREWETT. Witnesses:

F. GEORGE BARRY, HENRY C. THIEME. 

